package com.game.thrones.util;

import java.io.IOException;
import java.util.List;
import java.util.Map;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.fasterxml.jackson.databind.ObjectMapper;

public class JsonUtil {
	private Logger log = LoggerFactory.getLogger(getClass());
	private static ObjectMapper mapper;

	/**
	 * 获取ObjectMapper实例
	 * 
	 * @param createNew
	 *            方式：true，新实例；false,存在的mapper实例
	 * @return
	 */
	public static synchronized ObjectMapper getMapperInstance(boolean createNew) {
		if (createNew) {
			return new ObjectMapper();
		} else if (mapper == null) {
			mapper = new ObjectMapper();
		}
		return mapper;
	}

	/**
	 * 将java对象转换成json字符串
	 * 
	 * @param obj
	 *            准备转换的对象
	 * @return json字符串
	 * @throws Exception
	 */
	public static String beanToJson(Object obj) throws Exception {
		try {
			ObjectMapper objectMapper = getMapperInstance(false);
			String json = objectMapper.writeValueAsString(obj);
			return json;
		} catch (Exception e) {
			throw new Exception(e.getMessage());
		}
	}

	/**
	 * 将json字符串转换成java对象
	 * 
	 * @param json
	 *            准备转换的json字符串
	 * @param cls
	 *            准备转换的类
	 * @return
	 * @throws Exception
	 */
	public static Object jsonToBean(String json, Class<?> cls) throws Exception {
		try {
			ObjectMapper objectMapper = getMapperInstance(false);
			Object vo = objectMapper.readValue(json, cls);
			return vo;
		} catch (Exception e) {
			throw new Exception(e.getMessage());
		}
	}

	public static Map<String, Object> jsonToMap(String json) throws Exception {
		try {
			ObjectMapper objectMapper = getMapperInstance(false);
			Map<String, Object> vo = objectMapper.readValue(json, Map.class);
			return vo;
		} catch (Exception e) {
			throw new Exception(e.getMessage());
		}
	}

	public static List jsonToList(String json) throws Exception {
		try {
			ObjectMapper objectMapper = getMapperInstance(false);
			List vo = objectMapper.readValue(json, List.class);
			return vo;
		} catch (Exception e) {
			throw new Exception(e.getMessage());
		}
	}

	/**
	 * 将json字符串转换成java对象
	 * 
	 * @param json
	 *            准备转换的json字符串
	 * @param cls
	 *            准备转换的类
	 * @param createNew
	 *            ObjectMapper实例方式:true，新实例;false,存在的mapper实例
	 * @return
	 * @throws Exception
	 */
	public static Object jsonToBean(String json, Class<?> cls, Boolean createNew) throws Exception {
		try {
			ObjectMapper objectMapper = getMapperInstance(createNew);
			Object vo = objectMapper.readValue(json, cls);
			return vo;
		} catch (Exception e) {
			throw new Exception(e.getMessage());
		}
	}

	/**
	 * 
	 * @param list
	 * @return
	 * @throws Exception
	 */
	public static String listToJson(List<?> list) throws Exception {
		ObjectMapper objectMapper = getMapperInstance(false);
		try {
			return objectMapper.writeValueAsString(list);
		} catch (IOException e) {
			throw new Exception(e.getMessage());
		}
	}
}
